Latest / Uncomfortable Conversations with Josh Szeps / "Does Alien Life Exist?" with astrophysicist Dr Sara Webb

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"Does Alien Life Exist?" with astrophysicist Dr Sara Webb · Uncomfortable Conversations with Josh Szeps

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  G'day, humans! Welcome to the Safe Space for Dangerous Ideas, and it's the most dangerous
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  idea out there. The question of are we alone in the cosmos? You might have seen some reports
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  recently that suggest in fact we have just discovered we're not.
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  In a world more than 120 light years away, scientists say they've found the strongest
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  signs yet of extraterrestrial life. Astronomers detect a signature of life on a distant
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  planet. Signs of life on an exoplanet? What's up with that?
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  Being something of a nerd of the cosmos and alien life and sci-fi myself, I wanted to
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  get to the bottom of this with someone who I trust, who is an expert in this field, and
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  ponder not only on what exactly this latest discovery really means, but on all kinds of
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  things to do with whether we're alone in the cosmos. What the purpose of the cosmos
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  might be why it seems fine-tuned for life, whether or not life originated on planet Earth
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  or elsewhere in the galaxy, how we look for alien life, what we might be missing, why
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  we haven't found any. I wanted to address the Fermi paradox, which is basically this
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  conundrum about why if the conditions required for life to arise are as permissive as the
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  evidence on planet Earth seems to suggest they are, then why isn't extraterrestrial life
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  abundant and why isn't sufficiently common till it's been detected so far? The person
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  who I turn to for all such questions is Sarah Webb. She is an astrophysicist at Swinburne
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  University of Technology in Melbourne. She is really one of the rising stars of astrophysics
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  globally. She did her PhD in machine learning for processing astronomical data, which is
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  coming in particularly handy at this moment of artificial intelligence. She also runs
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  the microgravity experimentation unit at the space technology industry institute and gets
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  to send crazy things up into space. She has just gotten back from an all expenses paid
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  trip to the United States, organised by the State Department of the US, at least until
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  Elon takes his chainsaw to it, where she travelled to the Kennedy Space Centre in Florida
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  and met with other high-flying physicists and astrobiologists and all kinds of brainy
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  people. I love this conversation and if you're interested in the fate of humankind as it relates
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  to other civilizations in the cosmos, you will, too. The one, the only, Sarah Webb.
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  Oh, magical. I cried more a little time. That was great. That was fantastic. I think we
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  forget how many human works on getting us to the moon. Like 400,000 individuals made
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  that happen and I think at least for me as a scientist, the bit that I think is so beautiful
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  is all the trickle-down technology and the things that mean you use every day that
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  had to come from a programme like that. I love that. I was trying to show, I showed my
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  kids Apollo 13 and tried to impart to them what it would have been like before humans
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  had ever walked on the moon and they're only seven, so they're frankly more interested
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  in like the gadgets and widgets and like what it would have been like in the cockpit
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  when they were on the ground. Then they were, we had to turn off halfway through because
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  they were like, is that the worst thing that happens after the show, after all the power
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  goes out and they're stranded? They're like, does anyone die? Are there any more explosions?
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  I was like, just watch the movie. No, no. It's not impressive enough. I'm sorry. I'm
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  sorry. They're a tough crowd, man. They're harsh. So when we look for extraterrestrial life
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  on planets that are in our solar system, how do we look for it?
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  Oh, also lots of ways. This is probably one of the most fascinating things. You can
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  look for it in main two ways. One is called a biosignature. So you're looking for chemical
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  compositions that we know that we make here on Earth as living organisms. We're looking
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  for that. And then the other way is called a technosignature. So we're looking for signatures
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  that only intelligent. If we do ourselves intelligent and the intelligent things are able
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  to make and that normally comes in a form of radio signatures. Right. And those biosignatures
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  are a what? Are they basically breathing out and pooing and stuff or what?
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  All sorts. Yeah. So it could be things like the big one is death or die metal, die
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  guy sulfide or sulfide itself. So there's two forms of it. Both of them are made with
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  photoplankton. So it's oceans. It's living breathing ocean bacteria that really, it's
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  a formation of where life kind of came from on this Earth. And we know that if you find
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  that you're likely tuning with at least photoplankton and then likely other basic organisms,
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  the ideal of for other things as well. So one interesting one is actually looking for
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  carbon dioxide changes because we know that in our atmosphere our carbon dioxide levels
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  are changing and it's because of us. And so if an alien was say watching our sacred
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  over time, assume that maybe we are alive not only based on our other biosignatures, but
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  on the fact that we're producing this other chemical that isn't necessarily from us
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  living and breathing directly, but from what they were using on the Earth.
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  Right. And even if we weren't technologically sophisticated and pumping out carbon because
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  of our machines, we would be just because of living things do still living signatures
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  Yeah, right. Absolutely. Yeah, living on here here there and everywhere.
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  And so what it what what was this discovery that everybody is in a tizzy about at the moment
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  where supposedly we've discovered alien life. Tell me we have I wish I could like I really
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  wish that I could jump on here and be like we have found alien, but the reality is we haven't
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  not yet at least. So the TV and I think that was like fantastic word to use is over something
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  called DMS. So that was that that metal sulfite or that metal D sulfite that I mentioned
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  these two compounds that can only be made by life. Now what happened was that there's
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  this amazing exoplanet called K218B. It is an exoplanet that orbits a red dwarf, a little
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  bit of waste from our own solar system. And it's been of interest for several years now
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  because we think it's really interesting. It's big isn't the earth, but it might sit in
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  the habitable zone. So it might have a good water. We can't quite tell what it is. And the
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  authors of this specific paper are a very of the opinion that it is a Haitian world. So it's a
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  water world. And that would make sense if they think they found this signature that really
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  only occurs from Florida. You mentioned the habitable zone. What what's the habitable zone?
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  The habitable zone or the Goldilocks zone is this area around a star where liquid water can
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  survive on the surface. So we happen to live in the habitable zone of our of our sun. But if we
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  were any further out, say if we were at Jupiter, our earth wouldn't have a good water
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  on its surface. And same as if we're too close to just going away. You say we just happen to live
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  on it, but of course we don't happen to live on it. We could only live on it because it is here.
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  We could only live on it. We happily evolve to this beautiful planet.
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  There is no universe in which we're living on a world in which we can't live and are going.
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  Isn't it amazing that we live on a world where life is impossible?
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  By definition, it has to be what we have to be living in the habitable zone because we're
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  inhabiting it. So we go and looking at these planets that are in the Goldilocks zone where it's not
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  too cold that the water will be ice. And it's not so hot that the water would be steam. And then we
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  try to look for whether or not if there were water, liquid water on that planet, whether it might
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  contain life by analyzing the the gases or the changes in gases on the surface of that planet.
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  How do we see gases? How do we test? How do we know what the atmosphere is on something that is
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  so far away that it's just a tiny pin prick of light in the night sky?
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  So what we're able to do is use something called spectra of where we take light and we split
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  it into its very discrete wavelengths and we look for absorption or emission waves.
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  So this is either where you've got, say you have a certain gas and it might absorb a certain
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  energy level so you don't see that in the light or it might emit a certain energy level.
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  There's a beautiful example of what our sun looks like when you split it through the spectrum.
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  It's a beautiful rainbow with all of the black lines where there's absorption features.
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  So that's essentially what we're doing. The problem is that it's extremely, extremely difficult
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  to do it from here on Earth. We have our own atmosphere that gets in the way and the resolution
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  is really hard. So we can only really do it very well from space and that's where the James
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  Web Space Telescope comes in and it's able to not only take spectra but take it from space where we've
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  got this amazing resolution and look for these absorption and emission lines.
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  So the absorption and emission lines, just to clarify, I'm still a bit confused about how I
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  spectrometer, if that's what it's called, it even works because we're not talking about a star
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  here that's emitting its own light. We're talking about a planet that doesn't emit any light but
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  we're glimpsing light reflected from its nearest star are we and the wavelengths of that light are
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  different depending on what the gas composition of the atmosphere is or what. Yeah, we can do it in
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  two different ways. So one way that we can do it and the way that particular study that the
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  moment are doing it is you have a sun for pretend I'm the star and this is a planet. You take a
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  bunch of people listen to this and they don't watch the YouTube but I'm just going to say that
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  you're holding up a fist as if you were as if you were a star. Let's describe, let's describe it.
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  Yeah, yeah, okay, so there's a great deal of paint of paint and auditory picture for us Sarah.
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  I really, okay, so imagine you have a star and it is shining incredibly brightly and you take
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  the spectra of that star first and you take that and you split its light off and you get it
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  essentially. You then wait until you have the planet crossing front of the star so all the sun
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  that planet is now blocking out a little bit of that star light. Some of that light is also
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  traveling through that planet's atmosphere. So you're getting two things that are happening here.
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  You're getting an addition of light traveling through the planet's atmosphere that will contribute
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  to now this overall spectrum and then you wait for the planet to move away. You do essentially
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  subtraction of what you know the star looks like and this new data way the planet was in front of it
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  and you look for features that weren't there before. It's incredibly complex and incredibly precise
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  and this is why there's a little bit of controversy around this result because it's
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  it to maybe, it's a maybe and it's not announced on the coffin quite yet.
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  And often is it the case that we can't even see these planets at all and we're only inferring
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  there because they're so far away and they're so tiny that I don't emit their own light.
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  So the way we actually look for the planets is by looking for stars that just dim slightly and then
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  turn go get brighter and less bright and we assume that they're getting less bright because
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  a planet's passing in front of them and then we go all right well let's just
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  infer the existence of this hypothetical planet and then see if as it goes in front of the star
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  and dims the star a bit the star's light changes in its complexion implying that it's
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  traveling that the photons are traveling through the atmosphere of another body.
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  Yeah that's exactly right so what is incredible about that is that it's all inference
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  they're making it based on scientific hypothesis that because the light has dimmed we think
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  there's a planet there and we watch it dim over and over and we get these parameters that we think
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  can sound the existence of a planet but it's not like we're able to see that planet in great
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  detail so with this k2 18b the one that's causing all the controversy we have no idea what
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  it looks like we can't look at it and say yes you are an ocean world or yes you're a gas giant
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  or maybe you're a lava world you don't absolutely know and that's all you have to get all of those
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  little pieces it's almost like doing investigators um like you're investigating something yeah
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  forensics it's like the law or law and order yeah but law and order it's all systematic
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  and how do we know when we say that the the planets in the Goldilocks zone how would you know just
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  because the star that is its local sun is dimming and getting like lighter and darker where the
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  planet is it could be closer to us and big or it could be further away and smaller how do you know
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  how far from the star it is to infer that it's in the Goldilocks zone at all so we can use
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  catalyst laws we can go back to lovely catholic principles to to arm to determine the mass of
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  the planet that we think it is and then also its orbital mechanics around that star so we have
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  to see it pass in front of it multiple times to be able to get a really good estimate and then
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  based on the star itself that it's orbiting we know how much light those stars emit essentially
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  and then from there we can do the mass for how warm would it be for our sun is very different to
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  the majority of stars in our solar system our sun is actually very light and so if we were to
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  pick up the earth and put us near an m dwarf which are about 80% of the stars in our in our
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  galaxy we would freeze we would be too far away on that star even though for our one what we
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  happen to be perfect so it's a very it changes depending on your star it will change I'm quite
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  dramatically where life's in theory as we know it is able to form wait I thought our sun was a small star
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  small ish but about average what we call a man I'm just obsessed with having size that's larger than
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  everybody else okay I want us to start it in the top half she it's you can she's what we call a G
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  dwarf which is not representative we we call her a yellow yellow G dwarf star so the sun is makes
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  up about seven percent of the type of stars that we see in our galaxy and it in theory it's quite
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  tiny compared to some of the stars that we get out that we get ones that are absolutely enormous
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  that they're red in comparison to m dwarfs which you know 80% of the the star population
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  our sun bigger or smaller than the star that this new planet is orbiting bigger bigger yes
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  yes I want take that yeah we win take that we win so if there are aliens then we can engage in some
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  kind of a big swinging deck competition with these aliens and we will win oh absolutely yeah we
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  can put it on two shows our stars bigger than yours and exactly so just to clarify in terms of
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  the distance of the of the planet that we're in whose existence we're inferring on the basis of
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  the light from the star we know using where does the Kepler thing come in is that because we can
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  see the star wobbling or something as the planet goes around and infer what the gravitational
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  tug of the planet is or something like I'm still more clear about how we know where the
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  how far away from the star the planet is because if it was bigger it could be closer if it was
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  smaller it could be you know further away from us and it would still occlude to the light source
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  the same way yes so there's two key factors the tugging is one other method that's called
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  radial velocity but we can use gravitational influence to to determine it but just using the
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  blocking out of light what we do is it's a time period that that light is are dipping for so say
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  you have a dip that only lasts an hour then from there you can calculate will how big and how far
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  away do I think it has to be right to be true I see so it's lots of data collection and then
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  modeling based on that amazing scientists are clever aren't they so if we need to so what are the
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  potential other explanations for this discovery then if it's not life if you want to pour cold water
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  on it it might not be real it could just be a signal that is not that is not what we think it is
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  so what they've done essentially is taking this spectra they have found a slight absorption for
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  that little dip in the spectra and then they've modeled it to what they think TMS should look
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  like and then done statistics on that it's all it all sounds very very scientific but TLDI is
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  essentially it's like a kind of maybe match bit but it's not statistically at the confidence level
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  that if you're going to stand on a rooftop and say I have found aliens you wouldn't do it with
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  this confidence interval you'd be embarrassed so I think this is something that is you know it's
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  fascinating and we will hopefully get more and more data from it but I think as a science
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  communicator and scientist myself there's danger in proclaiming things too early I think and
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  what I was quite surprised with if I want to be really honest with this the way that it was handled
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  was the paper itself is a very measured very good scientific paper saying that this is what we
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  think we have found these are all the limitations and this is why it could not be true possibly
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  which is a good science paper you always leave things open that then the dichotomy of that was
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  that the first author had this ruining quote that essentially said that this is a water well
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  tinning with life and of course if you're media that's a fantastic thing how incredible is that
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  and I think that's where it's a little disappointing yeah I mean science is I too was excited
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  it is I wanted the aliens and this is one of the fields where you you can see how bad how how
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  illiterate most journalists are scientifically and how willing that they are to throw the board
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  the normal caution that they would apply to other issues like politics when it comes to issues
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  of science and they just there's so much clickbait and so much hysteria around it that I'm more
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  skeptical of mainstream science journalism than than many other fields of journalism it does
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  it do the bit disheartening unless we talk to the likes of you can go either way and thank you very
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  much which is why I do so and so would there be do we do we have the ability to detect life on a
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  planet of that size and that distance with a level of certainty that would have you saying that
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  you're your confident or is this just a limitation of our abilities I think very yes we do so
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  what would be confident for us is if this is going to sound extremely boring but it's something
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  called a five-segment detection it is when statistically your models are 99.9999 percent accurate
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  and that is a confidence interval that I think most scientists would say were very confident that
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  that signature is real in the data and then from day you say well what causes that signature it
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  can only be life therefore we're inferring with sound slice I mean that's a really that sounds
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  like a ridiculously live although 99.9990 percent like that's outright we don't expect for that level
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  of certainty in almost anything except for maybe aviation safety or something like you know I mean
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  what what what what a stress should be what percentage should we assign to the current one
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  is it as low as like when you say it's not certain does that mean it's 98 percent or does it mean
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  it's 70 percent it's still within it's just above 99 percent but it's not I know that I know
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  people do that and go oh my god you're saying there's a 99 percent chance we've discovered aliens
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  99 percent chance that the model matches the model they fitted but the cheeky thing with
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  Bayesian statistics is that if you actually break it all down there's a 27 percent chance that that
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  model model is isn't correct or doesn't correct it as well as we think so it's this is another
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  thing it's all really it's like you it's a numbers game of trying to describe very complex data
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  and I agree 99.9999 is an insane accuracy but when you're when you're thinking about things
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  such as trying to say that there's life out there in the universe it absolutely is the
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  certainty that I understand I understand that I mean I would be happy to take 99 percent instead
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  of 99.99 9 percent but once you throw in the red herring of there's a 27 percent chance that the
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  model is wrong that up that upends the apple cart completely it reminds me a little bit Sarah do
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  you remember in the I don't remember what this example was but if you ask a person in the street
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  this came up when in the case of DNA testing in criminal trials where yeah and though if you ask
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  a person in the street there's a one the odds of this DNA test not being accurate in implicating
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  the the convict or the accused is one in a million but the odds that the police mishandled it
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  and contaminated it and it's not the right DNA is one in a hundred so what do you think the total
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  risk of it being wrong is a layperson will say well it's probably somewhere between one in a
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  hundred and one in a million so it's probably like you know one in a half million or something like
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  that but of course that's wrong it's one in a hundred if it's if it's a one in a hundred chance
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  that DNA was contaminated then there's a one in a hundred chance that it's wrong so forget about
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  the one in a million altogether because like the day whether or not DNA is super accurate is irrelevant
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  if you're dealing with some knucklehead at gum shoe who accidentally you know had saliva on his hands
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  when he was handling the the test so this is a little bit like that we shouldn't think about 99
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  percent then we should think about 70 to 80 if we're talking about whether the model is 27 percent
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  likely not to be yeah true and not to not get excited this is this I like I live for the day
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  that I get to proclaim very excitedly that we're not alone in the universe because I'm off the
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  the team that there is absolutely alien life out there statistically it would be silly to think
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  that were the only ones enough in my own opinion it would be sad to think that this is it
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  this is it in the entire grand scheme of the universe earth is all we have so I you know I hope
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  that in a couple years time when we get more data more fitting and maybe we get that five sigma
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  cheek mark that we get to say that we've discovered alien life and that we're not alone I don't know
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  what that would do to the world chaos wise but I I personally I love to see that day honestly I
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  I mean if five or 10 15 years ago I would have said that it was going to it would upend everything
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  and now I feel like we're so insular and so absorbed by our petty squabbles that most people would be
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  like oh okay that's interesting it's a long way away yeah what's Trump doing but and so just
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  explain to me if it's possible to explain to a person who's scientifically illiterate where
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  the 27% uncertainty in the model derives from like what what could be wrong so it just could be
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  the model fitting itself so the the the statistical likelihood that the model is actually fitting it
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  you can almost imagine you're drawing you're drawing two lines and trying to make them fit so
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  there's something called Bayesian statistics and it's what we use a lot in a lot in lots of science
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  but in a strongly in particular to actually estimate how correct we are about a result so the
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  this still is a fantastic result and I think it's an excellent paper and really exciting
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  possibility but I think there's a couple of those those little red flags that I would be worried
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  about and one of the big ones I did mention especially for just the public's own scientific literacy
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  is so this is a discovery using the Jameson Space Telescope which is a NARFA asset but this
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  was not a NARSA press release and that might not mean much to a layperson but it's something
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  you've got to remember is where are the press releases coming from and who is backing
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  extraordinary claims I think that's the that's a big one because if this had been a you know
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  that 999.99% detection and everybody in the scientific community had the same consensus that
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  this was it NARSA would be backing that but that's that's not exactly what happened here and
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  so the are there any other red flags because I'm still unclear about the model and maybe it helps
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  to talk about what Bayesian Bayesian like my layperson's understanding of Bayesian reasoning is that
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  you insert into your adjudication of a probabilistic claim prior understanding of what
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  of the kind of probabilistic context of the claim itself right so if that makes any sense or someone
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  so maybe we can talk about yeah the claim that they made so what they did in the paper was that
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  they modeled what would it look like if the signature was this dms or the domethyl desulfides and
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  the sulfide or the desulfide two different elements and that's the two things that they
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  compared against they didn't do other models to say what happens if it was this other type of
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  chemical compound that has an emission or an absorption that's quite similar or what happens if
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  I try to match it to say carbon dioxide or any other type of um assumption so they get this
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  spectra and then they go does this fit the thing that we're looking for and they go it does but
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  they don't also say does it fit a whole bunch of other things that we're not looking for that sounds
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  like a cheat that sounds like the drunk man who's looking for his keys under the light and
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  under the lamp post because it's dark in spot where he looked for them like you truly have to
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  compare it against everything in order to come to a conclusion about the likelihood of one yeah and
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  there's another paper that came out um late last year or early this year where another team from
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  I believe it was the United States did exactly this on the exact same planet using their own JWS
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  and they have a beautiful plot that compares every I think they had eight different um compounds
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  that they were comparing the likelihood and they did not they did not confirm this DMS
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  detection or even I don't even think that they had a high life result of the carbon dioxide either
• 26:32
  so you can see that just from two different teams doing two different sets of analysis
• 26:36
  they're not agreeing and that is always a bit of a that's a publicly read slide number one
• 26:41
  in finance and that unless there's a consensus something something's not quite right so by
• 26:47
  which means it's more science to be done right and so when you say that the model has like you know
• 26:50
  whatever a 27% chance of being wrong what you're saying is that the assumption that the spectra
• 26:57
  that we see in the light that's passing from the star through the planet the assumption that that
• 27:02
  actually does represent the gases that we're talking about it has the potential to be wrong but if
• 27:07
  it's true that it does represent those gases then we're back to our 99% likelihood of those
• 27:12
  gases haven't been caused by life exactly it's almost like that DNA in handling question like which
• 27:19
  one do we think is correct but got it and where does this leave your optimism about this particular
• 27:25
  planet and how does this how does the likelihood of life on this planet compare to the likelihood
• 27:29
  of finding life on other planets that we might have as potential candidates
• 27:33
  dot the guy I really do think that this planet so k2 18b is probably one of the most exciting and
• 27:41
  it's probably one that if there is less this is one that we will confirm it on first because of
• 27:47
  the sheer amount of data we have on it and now every every scientist and a dog are going to be
• 27:53
  looking at it to try and get more data to contribute to this scientific debate and so I think it's
• 27:59
  a really good place to start the jury as I said is still out do we think it's the water world
• 28:03
  do we think it's the lava world is it a big gas giant a bit like that soon we don't know and there's
• 28:08
  still more that we can investigate on that so I personally I'm not counting it down and out yeah
• 28:14
  I think there's still a really good chance that maybe this this could be it um but there's also
• 28:20
  other ways we can look for life and I think one of the other really interesting ways that we try
• 28:25
  to look for life is the technosignature is actually looking the life that might be like us that
• 28:31
  is leaking radio signatures and that is something that would for me personally be just the nail
• 28:38
  in the coffin for intelligent life absolutely does it just out there yes that's obviously more
• 28:43
  exciting than it being like goo alky and goo yeah it's like yeah what would you take intelligence
• 28:51
  slime yeah we found slime we found living slime there's a slime covered planet and just you
• 28:59
  mentioned a lava a lava planet would it be consistent with the existence of life that produces
• 29:04
  this sort of sulfur if it was a lava planet lava doesn't seem very conducive to no so you're
• 29:09
  saying no lava is not conducive no no no okay got it um so technosignatures then let's just
• 29:15
  move on to that before we get to the big questions of like the Fermi paradox and you know why you
• 29:19
  still have faith that we're not alone yeah before we get there then what what what tools are we
• 29:26
  using and how are we scouring the skies to look for evidence of technologically advanced civilizations
• 29:33
  yeah so we're testing it so there's this program called break through listen and they're using
• 29:38
  some of the biggest telescopes including some here in Australia so the SK and the parks
• 29:43
  radio telescope to literally e-stroke in on planetary systems so to look at stars that we know
• 29:49
  planets exist or stars that we think there's a likelihood a planet will exist and just listen
• 29:55
  just listen for a couple of minutes here and there and what we're trying to do is look for anomalies
• 30:01
  in that radio data we're looking for things that have interesting modulations because when we
• 30:07
  record and when we emit radio data out it's very much decodable because it's the way that we do it we
• 30:14
  either do our frequency modulated or amplitude modulation things that we understand very well
• 30:19
  in terms of radio and that's what we're looking for and so far they've looked at thousands and
• 30:24
  thousands of stars and haven't found anything yet but there's billions and billions and billions of
• 30:30
  stars in our galaxy and it doesn't mean that they're not out there it just means the elements down
• 30:36
  and how systematically are we looking at this like are we literally just starting from one
• 30:40
  corner of the sky and going chugga chugga chugga chugga chugga down like an MRI scan would and
• 30:45
  looking at every single bit or are we using human intelligence to go well let's look at this
• 30:49
  bit and not that bit and then maybe we missed a bit here we're using our big human brains to list
• 30:55
  what we think is most likely so stars that are nearby are stars it's probably the most important
• 31:01
  because we're looking at stars that could have life on a similar scale to us so one limitation
• 31:08
  with radio signatures is that it's just light and it travels at the speed of light so say
• 31:14
  you've admitted a radio wave today it would take four and a half years until that radio wave
• 31:21
  reached our nearest solar neighbor which has been very long time so we want to look at stars
• 31:27
  that are nearby so within hundreds to maximum a thousand each light is away and even on that
• 31:34
  time scale there's a possibility that maybe we find a signature from life that no longer exists on
• 31:40
  it and certainly the other way around they might be looking for us and our radio signatures have
• 31:46
  been traveling a hundred and a bit used and they might not think that we exist yet just because our
• 31:52
  our radio signatures haven't reached then so there's a crazy way if we want to blow everybody's
• 31:58
  minds like we're 15-year-old stone as gazing at the sky I've heard some physicists suggest that
• 32:05
  if they were looking at our radio waves that are originated from this planet a hundred and
• 32:10
  fifty years ago they were right to say that there's no intelligent life technology
• 32:16
  advanced life on planet earth because there isn't yet there a regular time and space are
• 32:23
  relative and so in the time sleep that they inhabit it's true to say that it's 1850 we don't
• 32:29
  exist yeah or whatever exactly which is kind of crazy yeah it's not just the
• 32:35
  equations of the light it's that the traveling of the light is intrinsic to the existence of time
• 32:41
  in itself
• 32:44
  well frozen in our own little pockets of relatively
• 32:48
  relatively which I uh it really does hurt my brain sometimes when I fall asleep just thinking
• 32:54
  about the scale of everything I don't know if that's in me problem or in everybody
• 33:01
  I think it's in terms of some sort of wisdom I mean it's better than going to sleep thinking
• 33:04
  about Pokemon or lack of wisdom yeah I don't know and so the why are we assuming that
• 33:12
  that the the best window the best time window in which to catch an advanced civilization
• 33:18
  would be recently like isn't there enough time for advanced civilizations to have risen and fall
• 33:23
  on ten thousand years ago in our time and so it shouldn't really matter whether or not you know
• 33:28
  isn't it a bit parochial to assume that they would arise at the same time we do
• 33:32
  similar tasks yeah I guess it's not necessarily the best time it's probably what we're
• 33:38
  redeeming like a convenient time that we would exist within the similar time periods where we might
• 33:43
  be looking at stars that are saved ten thousand light years away and say we find a technosignature
• 33:50
  from that star that is now a very different place than it once was when that signature was released
• 33:55
  and we're a very different place then we want to have a home of communicating with that
• 34:00
  civilization because by the time they will be they will have moved on or died no not unless
• 34:05
  you've read the three-body problem and then we're all we're all in a problem a surprisingly good
• 34:12
  television adaptation as well did you ever see the the Netflix show I did I quite liked it yeah
• 34:19
  I thought it was good yeah good one to check out if you're a sci-fi nerd okay so all right so we're
• 34:24
  looking for all of this stuff I'm also tempted to ask whether or not artificial intelligence which
• 34:29
  a lot of people are really optimistic about in this is going to revolutionize the way that we're
• 34:33
  able to crunch all of this data and find inferences in you know signals in the noise how will that
• 34:40
  work yeah well it already is helping us has been for the last decade or so so and this is actually
• 34:47
  near and dear to my heart because it's what I do but with optical data as I use artificial
• 34:51
  intelligence to sift through and know some apps of optical data and we do the same thing in
• 34:57
  radio data so it helps us with dealing with the data volume so the amount of data that's coming in
• 35:03
  and just you can't have a human look at it it's physically impossible and so you can train AI
• 35:08
  algorithms to help flag things that are interesting of course as limitations but it is game changing
• 35:14
  out and would be a list not to be using it when you say you've been doing that for a decade it's
• 35:18
  only been three or four years that we've been able to get chat GPT to write recipes in the style
• 35:25
  of a Shakespeare sonnet or something so what do you mean by AI you just talking about school
• 35:30
  about computing power or what because that strikes me as a bit different running a computer program
• 35:35
  to find things is like a yeah we're talking about like classic machine learning so like a
• 35:42
  convolutional neural network or using something like unsupervised clustering algorithms so things that
• 35:49
  have in principle been around the decades the mathematics of them we got very good at it in the
• 35:55
  last decade also and chat GPT has just exploded in the last two years and that that's a large language
• 36:02
  model that uses this idea of really complicated node connections but the mathematics for how that
• 36:09
  works has been around for a long time so we've been using more simple model to yeah to look at data
• 36:15
  no exactly right you can use you can use much simple models so we are exploring how we could
• 36:20
  use things like large language models and something called vision large language model as well
• 36:26
  so we give it an image and get it to help so that's actually a project I'm working on at the moment
• 36:31
  with a couple of students is can that help us in astronomy and if so how and if not
• 36:39
  you know can we make it essentially and so what would that look like you feed it an image and
• 36:43
  what's the goal you feed it an image and then you feed it a question so I might feed it an
• 36:48
  image of say picture of a galaxy that I took and I might ask it a question if there is supernova
• 36:55
  in this galaxy and instead of me having to run algorithms to do the actual power would normally
• 37:01
  look for a supernovae it has been trained on examples and examples of it and it can say yes or no
• 37:08
  and then I can go from there a lot of other things yeah okay so it could be almost like one of
• 37:13
  those kids games where you have two cards and the picture looks almost exactly the same but there's
• 37:17
  one slight difference that you have to pick and the AI is doing is just ingesting hundreds of
• 37:22
  thousands of images of different galaxies and it's noticing things that a human wouldn't yeah which
• 37:27
  we get it to do anyway we have AI physics and say do that but without that human into into say so
• 37:33
  the able to actually talk to an interface like a human which is what we do with being
• 37:38
  fat chat GPT and you know other models so you can physically just say I have a question here it is
• 37:45
  and I think that is a bit of a barrier between having to physically write your algorithms which is
• 37:50
  what we do now and then getting anybody who might not have written those algorithms to actually
• 37:55
  use them I personally I'm I'm big on the obviously on the AI train of when they're used
• 38:02
  ethically they are so powerful and can really help us in a range of different ways if you're a
• 38:08
  betting person do you think that AI is going to change the game in terms of finding life like if
• 38:13
  you had to if you wanted to make a bet with me about the next 20 years do you think it's going to
• 38:18
  happen I would make that bet I bet you a doctor pepper my favorite beverage and also
• 38:27
  all the universe that there will be AI somewhere within the discovery of life whether it's a technosignature
• 38:34
  or biosignature there would be an AI algorithm used within that probably for model matching probably
• 38:40
  for looking for anomalies and things right but do you think that we'll get up we'll get a positive
• 38:44
  hit in the next 20 years I really hope so I want that doctor pepper so I'm going to say yes
• 38:51
  well I'm glad that you like the taste of foul medicine which is what doctor pepper tastes like
• 38:55
  to me foul fizzy cough syrup but we can it hasn't I don't know well that says about my childhood
• 39:02
  that I know as doctor pepper but you grew up here in Australia right I did it and there's no real
• 39:08
  doctor pepper here except for in boutique no no exactly so I bought when I came back from the US
• 39:14
  just a month ago I bought 25 kilos of it wait are you serious constant love to me yes 25
• 39:23
  liters of doctor pepper that's 75 cans of doctor pepper yeah yeah it was a suitcase in a
• 39:31
  you brought three cases of doctor pepper you are such a loser it's unbelievable I did not know
• 39:41
  this about you wow for someone with your pedigree that is embarrassing and shameful and I can't
• 39:46
  believe you just admit I know I should be ashamed and that's okay I will take that to the grave
• 39:51
  but then the two things I'm passionate about in life is doctor pepper and the fact that alien
• 39:55
  success okay maybe for sure all right when the aliens come I'm going to have them on my side
• 40:01
  about that when the doctor pepper was you're going to be roundly humiliated when they real when
• 40:05
  they tell you how foul it tastes so the question of the question of where your confidence in the
• 40:11
  existence of extraterrestrial life derives from is interesting because it is a bit depressing I feel
• 40:18
  that we've been hunting and it's not obvious that there's anything there I mentioned the Fermi
• 40:23
  paradox you know which is basically just the idea that if life is as spontaneous and readily
• 40:31
  emergent as it seems to be on planet earth then there should be where are they it's of life
• 40:37
  across the cosmos that is detectable but it's incredibly forkund here and totally barren out
• 40:44
  there so what gives how do you explain that yeah I think the my favorite way to explain this
• 40:52
  Fermi paradox is there's a theory called the great filter theory and it's this idea and this is
• 41:01
  the solution to the fact that we don't see life everywhere so Fermi and Rico Fermi who came up
• 41:06
  with this question over 60 years now sat down with colleagues at a table and just went well
• 41:12
  why why do we not see aliens but you know we we exist why shouldn't other people exist and it
• 41:19
  was a bit of a funny joke and then decades learned by we've we've been searching we've been doing
• 41:23
  what we call setty search for extraterrestrial intelligence for decades decades and decades and
• 41:29
  decades it's not a new thing and it's exactly what we said we see nothing so far nothing out there
• 41:35
  and so one solution to the fact that we're not seeing does the universe teaming with life everywhere
• 41:43
  is that there's a great filter and that we happen to be on the good side of the great filter
• 41:49
  now what the filter could be is any catastrophic event that could end life so say you're an
• 41:55
  early earth and you're forming and all of a sudden you were bombarded with asteroids that
• 42:01
  you know change your surface chemistry or bombarded so much that the life kind of evolved to a
• 42:07
  certain point or wipe out life to a certain degree or maybe it's an event where you are orbiting
• 42:14
  your star and your star has a massive solar flare that will wipe out early life and you just
• 42:20
  kind of evolve past this kind of hiccup point and the idea is maybe we did maybe life is very
• 42:28
  basic life teens everywhere and then dies very quickly and we just didn't and I think I'm in two
• 42:35
  minds of that I think that is it's an excellent theory in principle to why we don't see
• 42:43
  technostomatures everywhere why we just don't see intelligent life everywhere but also it's an
• 42:47
  incredibly depressing one that the universe could be very very hostile on the grand scheme of
• 42:55
  things and we got very lucky which is also quite humbling you're relating a fairly sunny picture
• 43:03
  of what the great filter might be by placing it so far in the past at the dawn of life
• 43:09
  other people that we might be before the great filter that's right or the great well if you
• 43:13
  want to stay mildly optimistic you might say that the great filter emerges as intelligent life
• 43:19
  develops civilizations but that generally speaking the kind of toolmaking intelligence that gives
• 43:27
  rise to civilizations also gives rise to to tools that destroy intelligent civilizations also
• 43:33
  100% weapons and warfare and climate chaos and things like that accandidates for great filters
• 43:39
  that we may have gone past maybe we weren't past maybe we you know but then yes maybe we have
• 43:49
  to wait and see what happens over the next 200 years to know whether or not we extinguish
• 43:52
  life on this planet in which case that would also be consistent with the Fermi paradox which is
• 43:56
  that actually there were heaps of intelligent civilizations but they never last for more than
• 44:00
  the blink of an eye because they snuff themselves out so we're not hearing from them
• 44:05
  yeah you're exactly right so I tend to be a positive optimist I try to be sometimes
• 44:11
  but that that is very much like the glass half empty of very much so we are and I think it's
• 44:19
  very true right now we're at a very critical point where humans have evolved technologically
• 44:25
  very very quickly from our industrial age to now technological revolution like fantastic for us
• 44:32
  look at everything that was been able to do look at what it's done to our planet and to societies
• 44:38
  really and I think we're at a really interesting point where that idea of the great filter
• 44:45
  would we haven't reached it could very much be true maybe intelligent civilizations
• 44:50
  just don't survive very well when they're too technologically advanced and I think that's also
• 44:57
  that is a good explanation for why you wouldn't find techno signatures when you look at the sky
• 45:02
  but the virtue of your more optimistic interpretation is that it's a better explanation for why we
• 45:08
  don't find biological markers because no matter what we do to the planet it's highly unlikely that
• 45:13
  we're going to annihilate all life on earth right we might annihilate human civilization and
• 45:18
  send us back to the Stone Age but they're still going to be cockroaches and they're still going
• 45:22
  to be shrews and like or shrewd sort of they're called the other little rodenty things running
• 45:27
  around and they're going to be emitting whatever they emit that would be visible by alien civilizations
• 45:32
  which is perhaps even though that's depressing in itself it does give credence to your claim that
• 45:38
  maybe we are special nonetheless for having gotten over some hump I mean maybe the great filter is
• 45:43
  the emergence of biological life in the first place I mean maybe it is really really really unlikely
• 45:49
  that inorganic compounds start replicating themselves and get you know get us off to the races
• 45:56
  in the in the first place how do you evaluate that probability yeah well and I think there's
• 46:03
  a lot of research that goes on to how do you take inorganic compounds and spontaneously essentially
• 46:10
  and it doesn't have to be carbon-based life which is what we are with this lovely carbon-based
• 46:15
  life and we know that in the very beginning of the earth it was a very interesting place it was
• 46:21
  a bit of a lava earth we had lots of different things that were happening we did have some bombardments
• 46:26
  and asteroids it also had some solar flares lots of different things that were seemingly just right
• 46:32
  for basic life to start for me but perhaps that isn't right on other planets and this is
• 46:39
  another big question is maybe looking for the wrong life maybe other types of life so there's
• 46:43
  the idea of silicon-based life could form elsewhere they might look very different their metabolism
• 46:49
  and how they metabolize chemicals be very different to us and we we don't have an example of that
• 46:56
  yet so that's also another possibility is maybe there's odds of life out there
• 47:03
  if you want to get all sci-fi just hope in like futuristic and silicon valley about it
• 47:08
  there's this other theory that maybe you know we're at a tipping point at which consciousness
• 47:13
  and sentience are going to be absorbed into machines and that we there will be sort of you know
• 47:19
  human machine interfaces and the singularity is near and we're all going to upload ourselves into
• 47:24
  computers and that we are we are a you know a caterpillar that will turn into the
• 47:28
  chrysalis of the butterfly of the new AI or whatever and so it's possible that biological
• 47:33
  is conceivable that biological life gives way to some sort of technology that is no longer
• 47:38
  emitting biological markers but is still sentient how do you evaluate that I um I'm quite
• 47:47
  singularity to it yeah I like uh love a good bit of sci-fi I think have you read I am Bob I am
• 47:53
  Legion no oh I think you'd love it hips and cast it and it's this idea of you just spawned
• 48:00
  consciousness from our own brains into a bazillion different computer systems and that's still life
• 48:07
  in theory um so I think that's quite an interesting take and I quite like the idea of
• 48:13
  or maybe life is teaning but it's not life as we want to work biologically maybe it's this
• 48:17
  computer generated life that's still somehow is intelligent I don't know
• 48:23
  still would that still emit technological markers like radio waves
• 48:28
  it would yes for depending on the computer systems that they were using you'd get markers
• 48:34
  based on how much compute power they needed to use because computers and super computers
• 48:39
  are exceptionally power hungry so unless they're using a hundred percent renewable energy
• 48:45
  they'd likely be using some type of similar to us they're we're not on renewables yet
• 48:51
  burning coal whatever it might be to get their energy and then you've also got heat signatures
• 48:57
  so it'd be very hard to do but in theory if you had a planet covered in super computers
• 49:03
  you could spot if you had good enough resolution where they were based on how hot
• 49:07
  that the area was getting because super computers got to keep very very cold
• 49:12
  we basically are evacuating heat from the area and creating heat sinks outside of where they are
• 49:18
  so that could be one way of spotting them but your resolution would have to be very good this
• 49:22
  would be a perfect star track exactly that's right and what about the idea that the universe
• 49:29
  is teeming with life but they're intentionally hiding I love this idea dish there's part of this
• 49:36
  is something called universe zoo and the idea that life is out there everywhere and they are
• 49:43
  watching us right now and I like oh these guys are too fragile to say hello to we can't let the
• 49:50
  move that we exist there maybe we are not stable enough maybe we are the zoo and I think to go
• 49:56
  for one space Odyssey the very ending if anyone hasn't seen that movie yet you've you've had decades
• 50:02
  you need to go watch it now but the very ending of that one interpretation is that
• 50:08
  he is essentially in a zoo aliens have collected him and they're observing this person as an
• 50:15
  oddity and talking about not the very final shot where he's a baby but when he shows up in the
• 50:20
  one hospital room the white room exactly yeah have you read the book Sarah? No I have you know that
• 50:30
  when they were working on the movie Kubrick was like going off in all these hair-brained
• 50:35
  directions and who's the writer do you remember who wrote it? No I need to go read this now
• 50:44
  but whoever wrote the screenplay was collaborating with a company I'm blanking on his name
• 50:48
  one of the great sci-fi writers of the 20th century was collaborating with Kubrick on the script
• 50:52
  and he was like this is too messy I think we need to we need the Bible for what the story is
• 50:56
  before we make the movie so he went off and wrote a wrote the book on the basis of the fact that
• 51:00
  they wanted to do the movie so it's like this this collaboration thing where the book and the
• 51:06
  movie were conceived at the same time rather than one of them being based on the other and the book
• 51:10
  is so much less pretentious and so much more clear in it's under in its explanation of what's
• 51:17
  going on than the movie is like the movie is very kind of Kubrick injecting his ambiguity into everything
• 51:25
  but the the book is quite is quite clear about what it's about what is happening in that final
• 51:31
  passage it's great what does the book says happening in the final passage I don't want to spoil it
• 51:36
  okay I'm going to go read it yeah I'm going to go read it yeah go on and everybody should it's great
• 51:41
  it's a short book and it's totally gripping um that's what I was doing I mean again I don't
• 51:47
  I had to be the person who's always like bringing the more negative and terrifying explanation
• 51:52
  you know I love it really awesome but the the the other the more negative interpretation of the
• 51:58
  everybody is hiding thesis is that we're in a dark forest and there are marauding monsters in
• 52:07
  the forest and anytime anyone um creates a campfire it gets raided by the marauding monsters and
• 52:14
  they all get killed so everyone is hunkering down quietly had drunk hiding the only people who
• 52:21
  survive are the people who make themselves small and invisible because there are civilisations
• 52:26
  that are bloodthirsty enough to extinguish anyone anyone's that they see um so yeah and look it's
• 52:32
  not tonight so it's not a terrible idea I think um I have opinions on that because I I think you
• 52:42
  are fascinating the idea of what would it take for a civilization to be so advanced that they
• 52:47
  could actually move that planet and there's one train of like philosophical thought that you'd
• 52:53
  have to be peaceful you would have to be a peaceful worldwide planet-wide peaceful civilization to
• 52:59
  actually get you shit together enough to off planet and I quite like that idea because I just
• 53:06
  respectfully to the earth right now that wouldn't happen we could not all work together to say move
• 53:13
  us off planet if we needed to do it right at this very moment it's too geopolitically complex
• 53:20
  everything's extremely complex we don't have stability even in things like um we have
• 53:25
  food insecurity and we have poverty and we're not as stable as a society planetary society would
• 53:32
  need to be to really thrive off planet and so this is my because when my toxic positivity coming
• 53:39
  back it is so I I know I need to work but it's it but I know I mean I get like I admire the instinct
• 53:46
  and at the same time it just doesn't pass the bullshit test for me in the sense that you know
• 53:52
  Spain did not have to be a perfect place for Christopher Columbus to arm a less leave and conquer
• 53:58
  the Americas and commit a genocide against indigenous people you know Nordic Britain in terms of
• 54:03
  the settling of Australia you know 100% right so you could be vicious and you could also go out
• 54:11
  and colonize other places which I think if I was again it feels kind of made a bit on another doctor
• 54:17
  pepper it probably be that that is more likely based on what we what we've seen from our own
• 54:23
  from our own history and in that sense I would like to touch on this because I think you'll find
• 54:27
  this interesting is that there's a huge debate of if we should intentionally book signatures out there
• 54:33
  so we're leaking radio waves all the time very low level leakage from TV stations radio stations
• 54:39
  for all things communication that we do and we're changing a lot of it to digital now but we still
• 54:44
  leak a lot we have though there's been I think five or six instances where we've directly used
• 54:51
  massive radio telescopes to send enormous signals vote signals with high power that can travel
• 54:58
  very far directly to other planets and there's a whole debate of is that a good idea or not and
• 55:06
  it's that dark forest situation because you're lighting a fire you're saying we are here and we are
• 55:11
  smart hello and you're hoping that anyone who picks up on them is kind and respects that and it
• 55:18
  kind of goes back to the three-bony propellants was this that a good idea or not yeah it seems
• 55:23
  crazy to me I mean that you would have to concede that there's at least a non-zero chance that
• 55:27
  they're hostile I mean if it was a 50 50 chance you would say don't do it I mean don't if there's
• 55:32
  a 50 50 chance that there's a murderer in the street across the road you don't turn your lights on
• 55:37
  and off and on and off and wave flags out the window going hello I'm here come and get me Mr.
• 55:42
  serial killer right and you know how low does the how low does the probability of there being a
• 55:48
  serial killer in the house across the road have to get before you start doing that I mean you want
• 55:52
  it to be you want to have some reason for being very confident before you start blasting
• 55:58
  broadcasts into the cost 100% and there's I debated with a colleague once about this who there
• 56:05
  can you know it's like what doesn't matter anyone who finds this is sort of far away that's
• 56:09
  going to take them hundreds of years to actually get to us doesn't matter sure but anyone who is
• 56:16
  very civilized and no potentially has figured out how to travel quite fast use resources quite well
• 56:23
  maybe that's not a problem for them so I'm more of the fence of the maybe we should be cautious
• 56:29
  optimistically cautious I want to look for techno signatures and I really want to discover
• 56:34
  and confirm that there is life out there but I also what is the possibility of other things
• 56:40
  and I think that's an interesting one yeah but again if there's a I mean if the civilization
• 56:44
  we're talking about is seven light years away and it's possible that these civilizations can
• 56:51
  travel at some significant percentage of the speed of light then we're only talking about maybe
• 56:55
  a few hundred years to get here and the same people who are telling you don't worry about it it's
• 57:02
  way far into the future would not say the same about climate change they would say no we have to
• 57:07
  care about what happens several hundred years right now great great great great great great children
• 57:11
  you know you know it's not just it's not good enough to say like well I'm going to be dead who cares
• 57:15
  what happens in 2350 well the people who are going to be alive in 2350 will care about whether or
• 57:19
  not they get invaded by aliens yeah exactly right it's exactly right and I think that's a whole
• 57:26
  kind of perception shift I guess of like what are we doing right now that will we won't we won't
• 57:35
  maybe see the consequences of see the rewards of but and I think that's a whole whole
• 57:40
  another debate of trying to realize that you know we need to think long long term just a human
• 57:47
  in general hard to do but yes should we settle other planets in our solar system like Mars
• 57:57
  and I think that settling I think it would be a terrible idea to actually try and and
• 58:05
  to move people like Elon's whole idea of we're just going to move and we're going to go set up a
• 58:11
  you know a civilization and we're going to leave happily I'm a laughter I just I don't think
• 58:15
  it's realistic I absolutely see that exploring other planets on short-term basis is very interesting
• 58:22
  and very exciting and the idea of sending astronauts to say two weeks at a time to get data that
• 58:28
  we otherwise could not get fantastic but action living off world has so many ethical problems and
• 58:36
  one of the big ones is and not a lot of people think about this but if we were to say settle on Mars
• 58:41
  and we were to start we're producing Martian the atmosphere is very different we'd have to have
• 58:48
  you know this whole biosphere but the gravity is very different again and they've done models to
• 58:53
  show that people developing from infancy off would likely end up with really really complex
• 59:00
  muscular skeletal problems and bowling of legs quite similar to um to what Polio used to do
• 59:07
  and have lifelong pretty much affection like affectedness from from living on a planet that we
• 59:15
  we haven't evolved to live on and so I personally myself this is particularly my only my only
• 59:22
  my only rant is that I think it's not responsible to go gone home um like what we're seeing some people
• 59:31
  do is that the only concern like if you could resolve that concern by I don't know if there was
• 59:36
  either a medical intervention or the people you know alternated their life between the surface of
• 59:41
  Mars and a you know one one point five exactly uh you know a spaceship that kind of equaled it
• 59:48
  out to about a hundred percent gravity on average on six monthly instance or something like that
• 59:53
  and they were free to come back to Earth if they wanted to then does that change your thinking about it?
• 1:00:00
  I don't think it changes it by much I think the effort it would like the effort it would take
• 1:00:05
  to set up a full settlement might not be worth the reward because I guess what I guess the reason
• 1:00:13
  is why would we why would we do it apart from wouldn't it be called via two planet civilization
• 1:00:20
  but I think there's a lot of things on and maybe on the hippie hippie and that's okay but there's
• 1:00:25
  I think for a lot of things on uh that we can use um you know resources and tower and and things
• 1:00:32
  like that to change first if that makes sense yeah I don't know I'm just not not a fan of Elon's
• 1:00:38
  approach at all I think I mean and that could be and take the man out of it though right like let's
• 1:00:43
  assume that the only one who's doing this it strikes me that there are two I understand there to be
• 1:00:47
  two main reasons for building a settlement on Mars one is the to hedge against existential risk
• 1:00:54
  and just to say like the long for our long term survival be it a pandemic or an asteroid strike
• 1:00:59
  or who knows what or a massive volcanic eruption that coats the planet in uh you know small
• 1:01:04
  gonna make agriculture impossible we should have there should be some people who aren't on this rock
• 1:01:09
  who are on other another rock who could start over um and then the other one just seems to be a more
• 1:01:15
  kind of almost philosophical one which is like if humankind is going to flourish over the course
• 1:01:21
  of millennia rather than merely years then at some point it's inevitable that we'll have to
• 1:01:28
  and interplanetary species because that is what success as a you know as an intelligence
• 1:01:33
  civilization would look like therefore we ought to retroactively do the things that we know we will
• 1:01:39
  have to have done in order to become successful you know now so that we make that so that we kind
• 1:01:45
  of give birth to that new phase of human civilization which seems as sort of weirdly kind of circular
• 1:01:50
  to me or most like it's total logical like we have to go to space because we have to go to space
• 1:01:54
  because if we don't go to space then we won't have gone to space um you know it's like in the future
• 1:02:00
  we will need to have gone to space and therefore we have to go to space now hang on a second
• 1:02:04
  where are we pulling ourselves up by our bootstraps here it's like we've just we've just accepted as a
• 1:02:09
  given that we're gonna end up in space and therefore we have to do it now um nonetheless I I feel
• 1:02:14
  the tug of that for sure and I also feel I just missiveness towards your critique about like there
• 1:02:20
  are things there are problems to solve here at home because you know they're always gonna be
• 1:02:24
  problems to solve here at home and you can always say that we should you can the same argument
• 1:02:28
  can be made from not going to the moon or for not investing in scientific research because
• 1:02:32
  there are starving people in sub-Saharan Africa and so we should invest all of our resources into
• 1:02:37
  mosquito nets to stop people from dying from malaria like these are these are all true enough
• 1:02:41
  statements as far as the ethicist is concerned but you also do cool shit I agree I'm very
• 1:02:48
  on the team of cool stuff is incredible and I think human translate my cool shit into cool stuff
• 1:02:54
  that's it is cool shit thank you I've got a list so sometimes I get nervous saying my
• 1:03:00
  okay okay I'll just I'll just psychologically swap every every instance of the word
• 1:03:05
  stuff to shit mentally you can say no I love it shit is great but yeah and I do agree that I
• 1:03:11
  think the humans do actually if we are going to thrive over millennium we will have to move
• 1:03:17
  from our planet because there's going to be a point and this is extremely extremely far in the
• 1:03:22
  future where Earth will no longer be habitable as our sun starts to die that's not for a billion
• 1:03:27
  or so years like an steedingly long amount of time but if humans or if civilization is going to
• 1:03:34
  survive we have to you have to move planet so I and I absolutely agree in the idea of it is
• 1:03:40
  very cool and it would be excellent to see and we're going to have to do it one day think my
• 1:03:45
  hesitancy is and it's probably going to own biases of like right and like thinking about if we
• 1:03:51
  had to do it right now so I think in the future and I think what's really really cool is the idea
• 1:03:57
  of human gaps of living underground on the moon and on Mars in lava tubes and I think that's
• 1:04:02
  probably one of the areas that I think would be the most real respectively are actually going to
• 1:04:07
  go and set up the civilization elsewhere probably wouldn't be on the surface would be underground
• 1:04:13
  and that would also be a very different experience of life than what we used to I want to see the stars
• 1:04:20
  I don't want to be underground if I'm underground that might as well be it might as well be in Arizona
• 1:04:24
  I mean you know I want to want to be I want to feel like I'm on Mars I don't want to be like I don't
• 1:04:28
  want to sign up for for the trip to Mars and then I wake up from the trip and I'm just seeing like you
• 1:04:33
  know this underground layer could be anywhere yeah screw that could be in kuba piti in an opal mine
• 1:04:40
  uh what do you think I don't know if you I don't know if you know the clip that has gone around a
• 1:04:45
  bit with uh Joe Rogan talking to the physicist about whether or not human life could have
• 1:04:50
  originated in the stars and how that might have to be yeah there might actually be species here who
• 1:04:58
  are who have been seeded here there was a group of scientists that were speculating that it's
• 1:05:04
  you know panspermy of the idea panspermy that it's possible that octopi had come from somewhere else
• 1:05:10
  some frozen eggs had actually come from somewhere else and landed on earth and these were like
• 1:05:15
  legitimate scientists they're contemplated not morons he says that octopus he says octopus
• 1:05:21
  might might be completely unrelated and Brian Green is like I think it's Brian no it's one
• 1:05:26
  clock so I think it's one of them he's like well um like octopuses are actually really similar to
• 1:05:31
  other I mean they look weird but they are biologically very similar in terms of their DNA I don't
• 1:05:36
  think they come from another planet um but what do you make of that whole conversation is that
• 1:05:41
  in any way legit um it's a legit theory it's a theory for sure it's a study of like it's
• 1:05:48
  called panspermy and it's the idea of you know maybe you have life whether it's basic
• 1:05:54
  microbes maybe it's you know maybe it's you know semi semi-advent life that is spread out across
• 1:06:02
  the cosmos by a kind of cosmic event so you could imagine one theory one theory that I do not
• 1:06:09
  think is correct but it's a fun one to listen to people really get passionate about is the
• 1:06:13
  hey cheer that life actually started on Mars and asteroid hit Mars and then whatever seeded that
• 1:06:19
  life hit Earth and then that that what happened um and you can think of it as that way it's like almost
• 1:06:24
  this trend sort of stuff literally stargust but in a more complex form things viewed across the
• 1:06:31
  cosmos um I think it's a really fun theory I think we don't have any evidence that is it would
• 1:06:38
  actually happen in principle because space is not kind at all to to organic life just radiation
• 1:06:46
  we've got the vacuum of space and I think it's fascinating but I think if it were to happen it
• 1:06:53
  would be on life that's probably not like us not like octopus so maybe it's like tide grades
• 1:06:58
  all something like that what's that they are the little water bears if you have a google water
• 1:07:04
  bear they're the tiny little microbes that look like the cutest freaking things in the world
• 1:07:09
  they have little tiny feet they have like a I don't even know like a little face they are adorable
• 1:07:15
  those are the aliens you're saying honestly that's probably the closest thing we would get is
• 1:07:21
  them surviving elsewhere because we've put them on the outside of the space station and they've
• 1:07:25
  survived they have the yeah we've dehydrated the shit out of them so you can take away like
• 1:07:32
  99% of their moisture completely dehydrate them and then rehydrate them and they re-enimate
• 1:07:38
  essentially you know they don't die but they re-enimate they're basically in a coma and you
• 1:07:43
  bring them back um they are hardy little creatures they can survive radiation like they're fantastic
• 1:07:50
  and they're tiny tongue tongue creatures and the outside of the space station I mean it doesn't get
• 1:07:55
  more inhospitable than that in terms of solar radiation absolutely solar radiation temperature
• 1:08:00
  changes like it's the awful environment and yeah they were a good chunk of them were able to survive
• 1:08:06
  to a certain degree is what's the advantage of the uh what is it perma spermia theory perma
• 1:08:14
  spermia theory what is it gain us because I don't understand why it's more likely that life would
• 1:08:18
  have evolved somewhere else in the galaxy and smashed into us or on Mars and smashed into us then
• 1:08:23
  spontaneously if like if life is spontaneously going to existence isn't it just as likely to have
• 1:08:28
  done so here as somewhere else yeah I'm on that camp that I think it was more likely to just
• 1:08:33
  spontaneously based on physics and biochemistry um I think it's just the theory that people love
• 1:08:41
  because it's interesting and it sounds very fun and it's kind of interesting where it's the idea
• 1:08:46
  of maybe you forget things of very similar RNA or DNA to us and I think the what would be for
• 1:08:54
  talking about alien life the coolest thing that we could possibly concede at least in wildlife time
• 1:09:00
  I think is actually finding microbes somewhere like your worker or somewhere like titan like a
• 1:09:06
  moon or Jupiter or sun so in our solar system but away from us and trying to understand
• 1:09:12
  are those microbes biologically very similar to us do we share similar DNA and RNA in that
• 1:09:19
  goes building block patterns or is it very very different and then I think then that perma
• 1:09:25
  conversation will come in more but if they are if they are related to us then you would have to
• 1:09:31
  assume they have the same source which is probably not on our planet if it's also elsewhere in the
• 1:09:36
  solar system could be also in the solar system which is very cool cool is true who knows I wouldn't
• 1:09:45
  bet a doctor paper on it certainly not three cases of it but you're smuggling through Australian
• 1:09:50
  customs I've just finished reading a book rostath that's book about religious belief in which he
• 1:09:56
  lays out the case for being a Christian a Catholic specifically and you know he goes through a lot
• 1:10:01
  of the conventional arguments that anyone who's done the philosophy of religion or you know who's
• 1:10:05
  dabbled in that knows and I wonder what you sort of think of I guess the fine-tuning argument is
• 1:10:11
  probably the the biggest one that it's just it's too improbable that we exist in possibles where
• 1:10:17
  all of these these necessary constants the dials essentially of the universe are set in such a way
• 1:10:23
  that it makes it possible for celestial bodies together in the way they do for things not to
• 1:10:29
  collapse in on themselves for a star to burn the way that they do and then to produce the things
• 1:10:33
  that we are then made out of and we assemble ourselves into thinking creatures like as far as
• 1:10:38
  he's concerned that is just far too fantastic all the story to think arose for no reason and so
• 1:10:44
  his most plausible reason is that there is a creative consciousness behind the universe who
• 1:10:49
  brought it into being and set the dials just so how do you grapple with that I think focusclerza
• 1:10:56
  I'm agnostic I I grew up going to a Catholic school and I actually I did really well at religion
• 1:11:04
  because I'm really like history really good but I myself my personal beliefs is I'm very agnostic
• 1:11:12
  where I don't think we have enough evidence either way for me personally to to make a decision
• 1:11:18
  and I possibly don't believe in or don't don't worship any single gods because I
• 1:11:25
  I am that agnostic kind of person and I think I've had conversations with lots of people about
• 1:11:30
  this specific fine tuning point before and my I guess my rebuttal or my devil's advocate is that
• 1:11:37
  it looks fine tuned to us because we exist in it in the universe but there's just as likely
• 1:11:45
  probability to say a idea to your god creating it then they're being an infinite amount of universes
• 1:11:53
  and this is just one of them that happens to have those particular physical parameters and I think
• 1:12:01
  that's where I lean is this idea of very much at an Auckland's razor type of girl even
• 1:12:09
  I do love Matthews law Auckland's razor ultimately takes the cake for most things malice where the
• 1:12:15
  simplest explanation often is the most true and at least in my mind existence happened therefore
• 1:12:23
  it did and I don't need to reconcile myself with it but I understand that I once do and I think
• 1:12:31
  that having beliefs and I'm a huge reponent in the freedom of belief because existing is really
• 1:12:37
  really bloody complicated like just being a conscious being is a lot nobody asks for this
• 1:12:45
  and we're all here trying to exist on this planet and I think trying to understand or reconcile
• 1:12:51
  with ourselves what that means looks very different to everybody so I understand that the positioning
• 1:12:57
  I guess but I myself I think the the agnostic position I think you're you're articulating two
• 1:13:08
  different things one is an agnostic position based on the axiomatic sort of fact of existence
• 1:13:14
  which is just to say yeah existence exists the way that it does and we can invent a whole lot of
• 1:13:18
  stories about why that might be or we can just accept the fact that we do live in this universe
• 1:13:24
  and we exist and you know so let's try to model through and to me that's a perfectly legitimate
• 1:13:30
  move but the other move that you're making I'm not sure is a sound which is to say that
• 1:13:36
  Auckland's razor would drive us to believe that there's an infinite multitude of invisible
• 1:13:41
  universes that and that that is a simpler explanation than that there's a creator who created
• 1:13:47
  this one but those both those both seem to me to be wild propositions both of them I think
• 1:13:54
  at least in my opinion could be equally true because we have no evidence against one or the other
• 1:14:00
  is that makes sense and so based on the fact that we don't know why our universe in this
• 1:14:06
  and the first place what was it that ceded that big bang and the idea that that big bang could
• 1:14:12
  have happened in a multitude of different areas and different universes um yeah I quite like
• 1:14:18
  that theory I guess it's probably not Auckland's razor in that sense but in other aspects of
• 1:14:23
  of life that's very much very conformals that yeah I mean it it strikes me as both convincing and
• 1:14:32
  also weirdly unsatisfying to say well of course of course we live I mean I sort of made this
• 1:14:38
  move earlier in the conversation but of course we live in the universe or on the planet where
• 1:14:42
  which is hospitable to us because if we didn't then we wouldn't be here to look at it then we wouldn't
• 1:14:46
  exist yeah Christopher Hitchens used to say that religious people saying marvelling at how well the
• 1:14:52
  the world is tailored for our life is a bit like the water in a puddle saying look how perfectly
• 1:14:58
  this puddle has been tailored to the exact shape of me the water like yeah the your shaped that way
• 1:15:04
  because the puddle is that way and if it wasn't a puddle you wouldn't be there to be remarking upon
• 1:15:09
  it yeah but and yet it still feels like a an unsatisfying dodge in some way it just it it I can't
• 1:15:17
  quite figure out what's wrong with it but something but my a little bullshit detector in my head
• 1:15:21
  sort of goes off and says like wouldn't that just be a way to retrospectively rule out or just
• 1:15:29
  wave away any incredible event by saying well of course it had to go that way because if it hadn't
• 1:15:35
  gone that way then we wouldn't be talking about it potentially I think that's true for a lot of
• 1:15:42
  thing I just I find it really hard to reconcile good you know if it is a creator so that the
• 1:15:52
  universe was created maybe it's a simulation and that too would be a creation in a different
• 1:15:57
  sense that say it is created I have a hard time reconciling that we would know which creator it was
• 1:16:06
  I guess and that's probably where my agnostic sense comes in where you know out of the
• 1:16:14
  hundred plus gods that you could believe in I'm not convinced that any one of them
• 1:16:19
  oh yeah I mean that's convincingly enough no of course that's the second move yeah totally
• 1:16:27
  that's the second move that the religious person makes that is the completely illegitimate move
• 1:16:32
  I think like you know the world is miraculous and too miraculous to explain without some sort of
• 1:16:37
  intent behind it therefore Mary was a virgin I'm sorry what
• 1:16:42
  you know that doesn't follow at all could I strap off with this I guess what's it because you
• 1:16:51
  could also go down the route of just being completely be atheist about it all and say absolutely
• 1:16:58
  not I guess the scientist in me I think when I was younger I was probably more of that atheism
• 1:17:03
  of I just don't believe therefore no but as I get older I think the scientist in me says long
• 1:17:10
  actually I can't prove one layer of the other hence I have to sit on the fence which I know
• 1:17:15
  people absolutely hate and I'm so sorry but I think that's that the real scientist in me is
• 1:17:22
  that agnostic bound and then you have all of the thought experiments that kind of pop up from it
• 1:17:30
  but I do I have one of my best friends is Christian and also an astronomer and I think
• 1:17:38
  the way that they reconcile it is actually quite beautiful because I asked flat out one so I was
• 1:17:43
  like how how like you know you're studying things that are billions and billions and billions
• 1:17:49
  of years old but what you are believing in right now is not necessarily saying that and they
• 1:17:57
  had a nice layer of saying well maybe we just science is an understanding what what God has created
• 1:18:04
  God hasn't described what's what the universe is or something like that and it was an
• 1:18:09
  interesting reconciliation in the mind I'm not I'm not you're not selling it in a way that I'm buying
• 1:18:14
  it Sarah that's not impressive that's not impressive to me no I mean I think it's perfectly
• 1:18:22
  legitimate as a scientist to rule out to to regard any commitment to a particular religious
• 1:18:27
  scripture and it's you know and what it and it's claims about history and cosmology as being
• 1:18:34
  invalid and I think it's legitimate to be an atheist towards the religions of the book
• 1:18:40
  but at the same time I assume that when you say you're agnostic you're talking about a deeper
• 1:18:44
  kind of question about whether or not it's not the question in yeah that is unknowable yeah
• 1:18:49
  what do you think the last question yeah sorry jump in
• 1:18:54
  no I was going to I was going to mention simulation but I think you might be mentioning it
• 1:18:57
  yep go for it what are the yeah what do you think the odds are that that you know
• 1:19:01
  the thing is I'm trying to a gigantic technological AI
• 1:19:07
  I think the odds are extremely low if they universe is like us so for our universe we would
• 1:19:13
  really struggle to actually simulate a universe like us based on how we can actually make
• 1:19:19
  computers and it's all about a fine detail of actually making electrons go even if you were to
• 1:19:25
  use qubits and use quantum the actual size of the computer and the amount of time it would take
• 1:19:32
  to eat the speed of water a speed of an electron to communicate it quest the mega super computer
• 1:19:37
  doesn't work to actually simulate how many parameters you need for a universe like us because our
• 1:19:42
  universe has just an obscene number of of elements in it but aren't you assuming that the top
• 1:19:53
  tier level of reality is composed you can be completely different yeah what if what if we're
• 1:19:59
  all of this is taking place inside the equivalent of an electron you know in some of the
• 1:20:05
  some other plan yeah so I think it's unlikely they're like us it could be likely if they can
• 1:20:11
  completely different physically but even so it still is a physical based universe as in
• 1:20:18
  we're bound by the laws of physics that's just what simulations are courage that says physics
• 1:20:23
  will say yes or no to this and that doesn't change what our life is and somehow that's actually
• 1:20:29
  very comforting to me and I don't mind it I would not be upset if we were a simulation the
• 1:20:36
  set of someone turned us off that was your rude but I wouldn't be upset if this happened to be
• 1:20:42
  a physical simulation in a different way certainly explain why there are no other civilizations
• 1:20:46
  in the in this huge cosmos they're just like they're looking at us and they gave us a big backdrop
• 1:20:52
  yeah we're just one giant since the wall it explains why I keep forgetting why I'm going to the fridge
• 1:20:59
  with the dot com's razor Sarah outcomes razor you're just getting old and daughtering
• 1:21:03
  Sarah it's lovely to see you again it's great to talk to you thanks for unpacking all of this with us